Control%20of%20Microorganisms%20by%20Antibiotics

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Control of Microorganisms by Antibiotics

• Weinberg, chapter 11

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Properties of an Ideal Antibiotic

1. Bacterial specificity
2. Should not produce resistant strains
3. Does not cause allergy or toxicity
4. Does not cause other side effects
5. Does not eliminate normal oral flora
6. Cost effective
7. Hence the ideal has not been found!

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Antibiotic Adjunctive Therapies

• Treatment of aggressive periodontal diseases,
  chronic periodontitis, refractory periodontitis
• Initial identification of pathogens
• Appropriate antibiotic selection
• Debridement should be carried out first
• Systemic antibiotics commonly prescribed
• tetracyclines, metronidazole
• amoxicillin, Augmentin, ampicillin
• ciprofloxacin, clindamycin
• Periostat (doxycycline)

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Systemic Use Concerns

• Common side effects
• Nausea, GI upset
• Diarrhea
• Rash
• Resistant bacteria
• Poor client compliance

• May be to broad spectrum
• Common oral manifestations
• Black hairy tongue
• Oral candidiasis

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Controlled Release Agents

• Work by suppressing destructive enzymes produced
  during inflammatory process or suppressing
  microbes
• Considered for localized periodontal sites
• Systems available include
• Actisite (tetracycline fiber)
• Atridox (doxycycline gel)
• Arestin (minocycline microsphere)

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Advantages of Controlled Release Agents

• Client compliance not an issue
• GCF concentration greater than serum levels
• Delivery is localized reduces systemic effects
• Reduced side effects

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Tetracycline

• Clinical Use
• Refractory periodontitis
• Localized aggressive periodontitis
• Growing trend to use combination therapies more
  effective
• Systemic local delivery systems

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Tetracycline

• Mechanism of action
• Bacteriostatic, broad spectrum
• More effective against gram-positive bacteria
• However, A.a. highly susceptible
• Non-antibacterial properties
• Inhibits production secretion of collagenase
• Inhibits bone resorption

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Tetracycline

• Mechanism of action
• Antibacterial properties
• Inhibits growth multiplication of bacteria
• Dosage
• 250 mg for 2 weeks

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Tetracycline Side Effects

• Intrinsic tooth staining
• GI upset, abdominal pain
• Diarrhea, vomiting
• Fungal overgrowth
• Resistant bacterial strains

• Interferes with bactericidal activity of
  penicillin's cephalosporins
• Reduces effect of BCP

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Actisite? Periodontal Fiber

• Clinical use
• Pockets measuring ? 5 mm, bleed on probing
• Localized treatment for sites that have not
  responded to previous mechanical therapy
• How supplied
• Cartons of 4 or 10 fibers
• 23 cm in length
• 12.7 mg tetracycline hydrochloride
• Stored at room temperature

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Actisite?

• Application
• Treat one quadrant or one side of mouth at a time
• Client may request anaesthesia
• Fiber inserted into pocket (circumferential or
  not)
• Takes about 10 minutes/tooth
• Some control of saliva
• Should contact pocket base

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Actisite?

• Application
• Sealed in place with adhesive
• Apply in thin even line along gingival margin
• Surgical dressing not necessary but has been used
• Removed 7-10 days after placement
• Curette and/or cotton pliers
• Fiber comes out in mass or pieces
• Debride areas as necessary
• Tissue may appear red following removal

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Actisite?

• Adverse effects
• Discomfort
• Local erythema
• Little systemic reaction
• Used with caution in client with history of
  candidiasis
• Application around 12 teeth may result in oral
  candidiasis

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Actisite?

• Client instructions
• Avoid brushing flossing
• Use antimicrobial rinse
• Use of CHX may have syngerstic effect
• Avoid hard or crunch foods, stick foods, chewing
  gum

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Actisite?

• Clinical Efficacy
• Reduction in bleeding on probing and pocket depth
• More significant reductions in deeper pockets
• Reduction in periodontal pathogens
• Effects of fiber on bone loss, tooth mobility or
  tooth loss not established

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Metronidazole

• Clinical use
• Refractory periodontitis (when combined with
  amoxicillin or Augmentin)
• Necrotizing ulcerative gingivitis
• Moderate severe periodontitis
• Aggressive periodontitis (LAP) when combined with
  amoxicillin or Augmentin
• Following perio surgery if barrier membranes in
  place suppresses P.g.

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Metronidazole

• Mechanism of action
• Bactericidal antimicrobial
• Disrupts DNA synthesis leading to cell death
• Selectively kills bacterial associated with
  periodontal disease
• Susceptible bacteria include
• Fusobacterium, Bacteroides
• Peptostreptococcus
• Treponema, Campylobacter
• Veillonella

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Metronidazole Side Effects

• GI disturbances
• Headache
• Dry mouth
• Candida infections
• Metallic taste

• Nausea, diarrhea
• Stomatitis
• Avoid alcohol when taking acute nausea,
  headache, vomiting
• May decrease effects of BCP

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Metronidazole

• Clinical Considerations
• GCF concentrations gt blood serum levels
• When combined with oral hygiene debridement
  beneficial effect on periodontitis
• Periodontal surgery may not be necessary
• Doxycycline may be substituted for metronidazole
• If client cant abstain from alcohol

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Before AfterTreatment with Metronidazole

• Probing depth of 6 mm

• Tissue shrinkage recession

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Before After Treatment with Metronidazole

• 6 mm probing depths

• Surgery has not been required

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Metronidazole

• Some evidence of bone gain client 2.5 years
  after initial debridement and use of metronidazole

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Metronidazole

• Dosage
• 250 mg tid for 7-10 days
• 500 mg bid for 1-2 weeks
• Doxycycline
• 100 mg per day or BID
• Metronidazole and amoxicillin or Augmentin
• 250 mg (of each) TID for 7-10 days

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Arestin?

• Clinical use
• Periodontitis with pockets ? 5 mm
• How supplied
• Box containing 2 trays each containing 12
  cartridges
• Cartridge contains 1 mg of minocycline
  (semisynthetic tetracycline derivative)
  microencapsulated in Poly dry powder
• Cartridge inserted into a cartridge handle

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Arestin ?

• Preparing for Arestin

Premeasured, premixed, no refrigeration necessary
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Arestin ?

• Mechanism of action
• Broad spectrum
• Bacteriostatic
• GCF levels maintained at high levels for at least
  14 days

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Arestin ?

• Application
• Insert tip to base of periodontal pocket
• Expel powder into pocket
• Bioadhesive microspheres activate adhere on
  contact with moisture
• Cartridge contains enough Arestin for one
  periodontal pocket
• Clinical trials 30 sites treated in less than
  10 minutes
• Dressings or adhesives not required

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Arestin ?

• Adverse effects
• Headache
• Pain
• Mouth ulceration
• Slu syndrome
• Stomatitis

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Arestin ?

• Client instructions
• Do not eat hard or sticky foods for 1 week
• Postpone brushing for 12 hours
• Do not use interproximal cleaning aids for 10
  days

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Arestin ?

• Clinical efficacy
• 27,000 sites treated, n748

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Arestin ?

• Clinical efficacy
• Arestin with debridement demonstrated 27 greater
  pocket reduction in molars compared to
  debridement alone
• Mean reduction of 2 mm (pockets 7 mm )
• Effective in furcations